The present invention relates to semiconductor fabrication, and more specifically, to carbon nanotube semiconductor device fabrication.
Current semiconductor fabrication is trending toward the use of carbon nanotubes (CNTs) as semiconductor device sizes decrease. Dielectrophoresis is a phenomenon in which a force is exerted on a dielectric particle when it is subjected to a non-uniform electric field, and has been used to arrange multilayers of CNTs, with either a low density or a higher density, into stacked arrangements. Multi-layer CNTs, however, cannot be utilized in semiconductor transistor devices because the multi-layer arrangement causes a screening effect that inhibits the gate electric field and prevents proper control of the transistor gate. Consequently, conventional dielectrophoresis methods have been unable assemble CNTs to achieve a desirable CNT pitch separation while avoiding multi-layer CNT formation.